real::detail::dynamic_program Struct Reference

This view is COPIED ON EVERY find_iter AND count_matches CALL, so its size is a per-call cost and growing it is a decision, not a detail. More...

Collaboration diagram for real::detail::dynamic_program:

Public Member Functions
constexpr program_view	view () const
	Returns a non-owning program_view over this program.

Public Attributes
std::vector< instr >	code
	The instruction stream (main program + lookaround sub-program regions).
std::vector< char_class >	classes
	Interned character classes.
std::vector< named_group >	names
	Named capture groups.
std::vector< lookaround_sub >	lookarounds
	Bounded lookaround sub-programs (regions of code).
std::vector< cp_class >	cp_classes
	Match-time code-point classes (for klass_cp).
std::vector< code_range >	cp_ranges
	Flat range buffer the cp_class slices index into.
std::vector< instr >	prefix_code
	IL: the inner-literal prefix sub-program (the part before the literal), for the reverse start-finder. Empty unless there is a required literal with a top-level prefix. Dynamic-only (not built during constant evaluation).
std::vector< char_class >	prefix_classes
	IL: classes for prefix_code.
std::vector< cp_class >	prefix_cp_classes
	IL: code-point classes (klass_cp) for prefix_code.
std::vector< code_range >	prefix_cp_ranges
	IL: flat range buffer for prefix_cp_classes.
std::uint16_t	slot_count {2}
	2 * (capture groups + 1).
bool	byte_mode {}
	flags::bytes mode.
bool	unicode_word {}
	\b \B \< \> use Unicode word-ness (text mode).
pattern_hints	hints
	Search-acceleration hints.
std::int32_t	codepoint_mark_ascii {-1}
	ASCII sub-class index of an emitted codepoint-class block (-1 = none).
std::int32_t	codepoint_mark_offset {-1}
	Where that block starts (program offset); the whole-pattern hint requires offset 1.
std::int32_t	codepoint_mark_end {-1}
	Program offset right after that block ends (-1 = none).

Detailed Description

This view is COPIED ON EVERY find_iter AND count_matches CALL, so its size is a per-call cost and growing it is a decision, not a detail.

A ceiling rather than a stopwatch, and that is the point. A per-call cost of this shape is fixed: it does not scale with the subject, so it hides under the noise floor of any throughput row and surfaces only on short inputs. Timing cannot guard it – the effect is the same order as the floor of the rows that would carry it – so it is guarded by COUNTING bytes instead, the same way per-call allocations are guarded by counting them rather than timing them.

The number is not a target to hit but a line to notice crossing: ten spans plus pattern_hints plus the scalars and pointers. Lower it when the view shrinks, and raise it only with the reason written down – a change that adds a span here charges every call on both surfaces.

Guarded on the pointer width because std::span is two pointers: a literal byte count would fail on a 32-bit target for no reason (this project has a win32-narrowing CI leg), and the concern – do not silently make the per-call copy bigger – is the same on any width.

Owning, heap-allocated program: the storage backing real::regex.

Member Function Documentation

view()

constexpr program_view real::detail::dynamic_program::view ( ) const

inlineconstexpr

Returns a non-owning program_view over this program.

Returns

The view; valid as long as this program is alive and unmodified.

---

The documentation for this struct was generated from the following file:

• include/real/core/program.hpp